there’s a load of threads on the r1 forum about taking the cat out of the y-pipe. prob is they’re too busy calling each other names to actually put any real content into the rediculous 100 post-long ‘your mumma’ contest
was wondering if anyone had any solid info on this here? flatout - you did this right?
arguement for: apparently ripping out the metal mesh means potentially more airflow, and less heat in general, and particularly when stopped. maybe a couple of horses. deeper sound
against: the chamber that has the cat was designed with it in place, and having it empty means there is a swirling effect of the air and it doesn’t pass through cleanly. modding makes no diff to performance or heat when riding
basically is it just a waste of valueable tv watching time, or worth getting the rubber hammer and chisel out
You gain about 1 HP if that and the sound difference is barely noticeable from what I’ve heard.
Downside is that you lose exhaust back pressure and a slight drop in torque because the pipe is wider now and the gas flow changed.
Aftermarket Y pipes without cats compensate for this by being narrower where there would be a cat on the OEM Y pipe.
A lot of this is from what I’ve been told, but in my opinion, it’s a bit of a pointless exercise…Just get an aftermarket y pipe off ebay if you really need 1 HP.
slightly different bike - but I was talking to a bloke at a KTM dealership about a superduke…
first thing he recommended doing was replacing the exhaust cans - cause there’s a v.large cat in there… he said part of the reason is heat build up…
…if you have a look under the rear of a KTM superduke and see the heat clading round the cans - he’s not joking…
(I was asking him about trying to put a tailpack on the seat - he seemed to think that the bungees keeping the pack on would melt on the protectors covering the cans…)
other benefits include a lot more freely breathing engine too…
The thing is, it’s not like the old days when adding a pipe will net you big gains in HP. Well you seem to still be able to do that on Suzuki’s latest K7 Gixxer Thou, but that points to the recent tougher Euro 3 emission laws. I’d imagine the 07 R1 with it’s dual cat converters would be a similar issue when you swap out the y pipe.
On the 04-06 R1 however, that’s not the same. The original exhaust cans are already very good, especially when you convert them by removing the internal baffling. The cat converter is also well engineered and the bike loses very little power because of it.
You have to think that manufacturers spend millions engineering these bikes…Everything you change has a consequence.
That’s not to say that you can’t improve on the OEM gear, but if the gain is miniscule then why bother.
Also, the heat issue on the R1 is not caused by the cat. I find its the way the heat is blown upwards by the fans and the way air flows around the bodywork.
some good points mate. slight quibble on the manufacturers design part - they design it to be sold as a road bike meeting strict emissions regs. somethign i personally dont give a monkeys about. otherwise there would be no need for race parts eh?
exactly the point mate - if its miniscule its not worth doing. if its noticeable its not a lot of effort
anyone tested out the theory on the cat and whether its free horsepower for a very simple mod, a waste of time or even a detriment? R1 in particular naturally but anything similar
Racing is a different environment though mate and racers have different needs to street riders…The whole race this and that added to the names of bike parts sold to street riders is generally one of those bullsh*t / hype bike things…Like scraping pegs and chicken strips.
Race teams put on more than just a gutted y pipe and free flowing cans.
A full system is used and they remove the EXUP valve too because racers are generally on the power a lot more than street riders so don’t feel the midrange loss so much.
An R1 modified in the same way on the street would feel a bit naff…There’s already a limited amount of pull from low down the rev range.
“Race teams put on more than just a gutted y pipe and free flowing cans.”
and there was i thinking the rest was just the stickers. no sh*t sherlock
i think you’re confusing ‘tuning for outright top end’, and tuning. you can give the r1 way more midrange with aftermarket parts if you want to, just a question of how much you want to spend, and how much top end you’re prepared to lose in the process. anyway, back to the actual topic…
You made the dozy comparisson between race and street you slag
If you read that thread on the R1 forum, someone mentions that the gains aren’t that great but the Americans, given more oppurtunities to add to the carbon content in the Earth’s atmosphere, decided it was a ‘great mod’ anyway.
It depends on how much time you have on hands…You don’t lose much or gain much…
lol, this is turning into another r1 thread (i have read them already afro, thats why i was trying here). lots of opinion, no fact or first hand experience
